const { Transform } = require ( 'stream' );

const commaSplitter = new Transform ( {
                                          readableObjectMode: true,

                                          transform ( chunk, encoding, callback ) {
                                              this.push ( chunk.toString ().trim ().split ( ',' ) );
                                              callback ();
                                          }
                                      } );

const arrayToObject = new Transform ( {
                                          readableObjectMode: true,
                                          writableObjectMode: true,

                                          transform ( chunk, encoding, callback ) {
                                              const obj = {};
                                              for ( let i = 0 ; i < chunk.length ; i += 2 ) {
                                                  obj[chunk[i]] = chunk[i + 1];
                                              }
                                              this.push ( obj );
                                              callback ();
                                          }
                                      } );

const objectToString = new Transform ( {
                                           writableObjectMode: true,

                                           transform ( chunk, encoding, callback ) {
                                               this.push ( JSON.stringify ( chunk ) + '\n' );
                                               callback ();
                                           }
                                       } );

process.stdin.push( 'a,b,c,d' );

process.stdin
    .pipe ( commaSplitter )
    .pipe ( arrayToObject )
    .pipe ( objectToString )
    .pipe ( process.stdout );